21994338959 has 4 divisors (see below), whose sum is σ = 21994889880. Its totient is φ = 21993788040.

The previous prime is 21994338943. The next prime is 21994338979. The reversal of 21994338959 is 95983349912.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21994338959 - 2⁴ = 21994338943 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21994338979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 210464 + ... + 297125.

It is an arithmetic number, because the mean of its divisors is an integer number (5498722470).

Almost surely, 2^21994338959 is an apocalyptic number.

21994338959 is a deficient number, since it is larger than the sum of its proper divisors (550921).

21994338959 is an equidigital number, since it uses as much as digits as its factorization.

21994338959 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 550920.

The product of its digits is 18895680, while the sum is 62.

The spelling of 21994338959 in words is "twenty-one billion, nine hundred ninety-four million, three hundred thirty-eight thousand, nine hundred fifty-nine".